Method
What Insurek works out, and where the numbers come from
The rule
Under the compulsory health insurance an adult pays three things: the premium, twelve times a year; their own costs up to the deductible they chose; and above that, 10% of what follows, but never more than 700 francs a year. Nothing else. The benefits themselves are set by law and identical at every insurer.
Hence the only formula needed:
cost(spending) = premium × 12 + min(spending, deductible) + min(10% × max(0, spending − deductible), 700)
Where the numbers come from
From the Federal Office of Public Health, the “Health insurance premiums” dataset on opendata.swiss — the very source the federal premium calculator is built on. It holds every approved premium of every insurer: by canton, premium region, age class, model, accident cover and deductible. To that are added the federal premium-region table, which turns a postcode into a canton and a region, and the register of admitted insurers, for the names.
The data is downloaded once a year and turned into static files, here on the site. Nothing is queried while you use it: no scraper, no third-party server, no waiting.
What Insurek does not do
It sells nothing and refers no one: no commission, no partnership, no favoured insurer. It stores nothing: what you type never leaves your browser, because there is nobody to send it to. It knows nothing about your health beyond the figure you type yourself.
And it is not advice. It is arithmetic on public numbers: the premiums are exact, the formula is above, and the code is on GitHub for anyone who wants to check. Whether an alternative model suits you, and whether next year’s spending will look like this year’s, only you can say.
What is still missing
Minors: their deductibles run from 0 to 600 francs, co-insurance is capped at 350, and family discounts apply. Different rules, and handling them badly would be worse than not handling them. The same goes for premiums for people insured in the EU and EFTA, and for cantonal premium reductions.